Hermione gets to wear jeans and - ugh - hold hands with Ron. Harry is one angry wizard. And his supernatural foes are even more ominous this time, reports Claudia Puig

As Alfonso Cuarón, its director, puts the final touches to Harry Potter And The Prisoner Of Azkaban, it's clear that some things are the same about this Harry Potter and that some things are very different.

In the third of J. K. Rowling's books to be turned into a film, which is due out in the summer, he's still a wizard, of course. He still attends Hogwarts, and Ron and Hermione remain his best pals. He continues to wear those nerdy glasses. But the children are lankier, their hairstyles cooler and they spend more time in jeans and sweatshirts than in their school robes. "It took me three films to get Hermione in jeans," says Emma Watson, who plays her. "To get out of the robes with the tights and the itchy jumpers. Whoo-hoo!"

Before filming started Cuarón asked the young actors to write an essay about their characters and themselves. "The kids were very brave," he says. "They bared their souls. They were very eloquent. At some point I wanted to publish them, then I thought no, I promised them it was just for the work of the film, and it's their personal stuff."

And they held free-flowing discussions "about what it means to be 13", Cuarón says. "How it's different from 12 or 11. It's an archetypal age. Kids change so much. You want to change the way you dress, the way you look, the way you argue." In Azkaban, a moodier Harry is forced to face up to challenges much worse than the onset of the teen years. It will be a darker movie, both visually and in tone. And with a new director in Cuarón - Chris Columbus directed the first two adaptations - the film's focus will be on characters and rich visual details as much as on special effects and magic. There are demons within and without in Harry's world this time around.

As Harry and his friends return to Hogwarts School of Witchcraft and Wizardry for their third year they are plunged into the mystery surrounding a notorious escaped prisoner who poses a threat to Harry. Our wizardly hero must also face his own fears of death and despair in the form of the ghoulish dementors and spooky omens predicting his demise.

"This is my favorite of the books," says Daniel Radcliffe, now 14, who plays Harry. "It's a weird one because it almost reinvents the character. He's more hostile. He's got a lot of teenage aggression, which all people at 13 do."

The hormonal changes that come with being a teen will be visible on screen, and they're also evident in exchanges between the young actors on the set. There's much discussion of crushes and break-ups. Watson interrupted an interview to share a whispered gossip with a crew member about a cute guy.

When Hermione takes Ron's hand in a scene, Watson makes a quintessential 13-year-old grimace. The movie called for "some embarrassing hugging to be done. With Ron [played by Rupert Grint\]. We have a kind of a love-hate relationship".

For movie-goers it has been a love-love relationship with Potter and his pals. The new film's darkness may test that passion, at least for younger fans. Harry's journey in the third instalment begins with the terrifying announcement that Sirius Black (Gary Oldman), a convict believed to have killed Harry's parents, is on the loose and likely has his sights on Harry next. "This really shakes him as a person," says Radcliffe.

Harry is constantly looking over his shoulder for Black and living in fear of the inhuman dementors that suck the joy out of anyone coming into contact with them. They are placed as guards at Hogwarts to protect Harry and the student body from a surprise visit from Black. Rowling has called the dementors the physical manifestation of depression.

"The first movies were action-adventure films, with big chases," says Stuart Craig, the production designer on all three. "This film is concerned with confronting their innermost fears." Cuarón says: "Harry's always been a kind of outsider, but now he becomes more aware of that forlornness. It's about accepting who he is."

Harry has already come to terms with his magical powers, but being a teenager is no easier for him than for the average Muggle. "He's now becoming slightly more used to things like seeing a giant squid in a lake and all this magical stuff around him, the ghosts and everything," says Radcliffe. "Whereas at first it was completely amazing, it's now more commonplace. He's becoming slightly more relaxed in terms of how he deals with school, but he's a lot more paranoid about how he interacts with people."

Cuarón most recently directed Y Tu Mamá También, the Spanish-language film about two teenage boys and their sexual yearnings and adventures while on a road trip through Mexico. He sees Potter as a distant, younger, PG-rated cousin of those randy lads.

"Obviously the tone of the movies is completely different," says Cuarón. "Y Tu Mama was very realistic, with social observation. Here it's a magic world, a fantasy, a bigger canvas. But emotionally it's exactly the same thing. It's a journey of a character's seeking his identity and accepting who he is. To step out of the shadow of his father, for instance, is one of the themes."

And, as in the non-magical world, the characters' emotional lives have more intensity. "The hormones are buzzing, and so is their anger about things," says Cuarón. "And rather than repressing those things it's about letting it flow. It's not about encouraging it but just letting it be. I didn't want those emotions very polished. Sometimes they got carried away. I would let them. I didn't want them to be neat. I wanted it a little raw."

The Mexican-born director, who also made the acclaimed A Little Princess, from 1995, has allowed his Latin American heritage to gently imbue the magical atmosphere. "In his heart and in his soul he has magic and a sense of wonder," says David Heyman, one of the film's producers. "There's a Latin spirit here, a magical realism. It's a bit intangible but oh so seductive."

Light, or lack of it, will play an important part in the film. Cuaróhas created a distinctly different look, with the colours darker and more muted, the music more haunting and the tone edgier.

There are more wide-angle shots than in the first two films, to heighten the sense of drama, says cinematographer Michael Seresin. "The story is more dramatic, so the lighting is more dramatic, high contrast, more shadows. It has a very different look and feel from the previous films."

And there will be visual treats for the careful viewer. "There are lots of extraneous little bits of magic appearing in the background," says Craig. "Strange animals that live in Hagrid's hut, for example. There's somebody's tail poking through the floor. They're real throwaways, but there's extra richness, extra detail in these wide shots."

Hagrid's hut has expanded from a one-room shack to two rooms. His bedroom has teddy bears and fur skins. His living area is decorated with hanging pots and pans, as well as oversized chairs to fit his gargantuan frame.

In addition to Hagrid's expanded quarters there are new characters: Oldman as Black, David Thewlis as the werewolf Professor Lupin and Emma Thompson as Madame Trelawney, the ethereal divination teacher with long wavy gray hair, flowing gowns and a spacy manner.

A visit to the magical village of Hogsmeade reveals colourful Victorian-style shopfronts. At the students' favourite sweet-shop hangout, Honeydukes, Cuarón has added coconut clusters and lollipops from his native Mexico to the mix of sweets available at the shop.

There's no need to worry that any of the characters will turn saccharine this time around, however. The bookish Hermione strays a bit more from her studies in this movie. "This is a real girl-power film," says Heyman. "Hermione helps and leads Harry on many occasions."

She decks Harry's Hogwarts foe, the ultra-obnoxious Draco Malfoy, after he sneeringly insults her mixed heritage (she'sa wizard with human parents) and nearly causes the execution of a harmless hippogriff. After Hermione slugs Malfoy she exclaims: "That felt good!"

It's a move that Azkaban audiences are likely to cheer, and the punch proved therapeutic in easing Emma Watson's newly developed teen angst. "It was great fun," she says. "We did a couple of takes, and I was saying come on, come on, let's do it again." ... - USA Today Service

Harry Potter And The Prisoner of Azkaban is due to open in June